He is mates with this girl’s older brother who brought her along as, otherwise, she would have been home alone.

I’m 21 but we got talking at the party, then became friends on social media and got on brilliantly.

Last weekend she came round when I had the house to myself, as my parents were away. We planned to watch some movies and play on my Xbox but we ended up snuggled together on the settee watching a horror movie.

She clung to me in a scary bit, I hugged her closer and suddenly we were kissing.

She’s told her friends we had sex together and that quickly got around to my friends

She was just as keen as me and it ended up with us having fantastic sex right there on the sitting room floor. It was the most amazing experience of my life.

I’ve been in and out of relationships in the past but I’d love to settle down with this girl — and it’s what she wants, too.

I want to tell the world but, most of all, I want to tell her parents so we don’t have to sneak around.

She says they won’t accept us being together but I reckon nothing can stop us having a future together so long as we love each other.

She’s told her friends we had sex together and that quickly got around to my friends. Now they’re saying she’s jailbait and I’m a paedophile. My intentions towards her are good and I’m not just after her for sex.

How can I make everyone believe me and give us a chance?

DEIDRE SAYS: No matter how honourable your intentions, you are breaking the law by having sex with an underage girl.

The law is there for a reason.

Younger teenagers don’t have the maturity of judgment to know whether it is in their best interests long-term to have sex with someone, with all the risks and responsibilities that brings.

You’ve fallen for one another but it’s very early days.

At 15 she could feel entirely differently in a month or two.

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How can I get my best friend to leave her poisonous boyfriend?

So take it carefully and responsibly for now.

Tell her it’s wrong to sneak around. Say you want to meet her parents so you can explain you will not abuse their trust – and that means no more sex until she is at least 16.

If you can’t keep that promise, then you must walk away now – for your sake as well as hers.

My free leaflet on Under-age Sex will help you understand why.

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